Diagnosis, General [CA]

Any microcomputer-based system can run diagnosis to Volvo standards: this includes ABS and TRACS.

There are two DTMs, self-test and activation. Self-test means individual electronics systems run tests while they are on and post DTCs for reading off at a later date.

The self-test function is designed to:

- discover faults and post the appropriate DTCs.

- identify faults in the electronics system.

- display coded messages indicating the type of fault.

Activation is used to:

- change the speed at which diagnostic information is transmitted when using Volvo Scan Tool (Diagnostic Key) or Volvo Scan Tool (System Tester).





Diagnosis and readouts are made via the DLC in the engine compartment. DTCs can be read out, interpreted and displayed as plain text using the Volvo Scan Tool (Diagnostic Key), Volvo Scan Tool (System Tester) with memory module for plain text readouts or read manually as codes via position 3 of DLC A and interpreted using the DTC tables in this service manual.

DLC A has a black casing, while DLC B is grey. Both DLCs have black covers. DLC A is a standard DLC with selector cable, LED and buttons for selecting DTMs.

DLC B, on the other hand only contains some positions. This means that, when fault-tracing any system connected to DLC B, you will need to use the selector cable and push-buttons from DLC A.